Tuberculous Lymphadenitis

Tuberculous lymphadenitis is the most common form of extrapulmonary tuberculosis in children, accounting for approximately 30-40% of extrapulmonary cases.

Epidemiology:

Age distribution:
- Peak incidence: 2-12 years
- Higher risk in under-5 age group
- Different presentation patterns by age
Geographic distribution:
- Endemic in developing countries
- Rising incidence in developed nations
- Association with HIV prevalence

Risk Factors:

Primary:
- Close TB contact
- HIV infection
- Malnutrition
- Young age
Secondary:
- Immunodeficiency disorders
- Chronic diseases
- Environmental factors
- Genetic susceptibility

Pathophysiology

Mechanism of Infection:

Primary routes:
- Lymphatic spread from primary focus
- Hematogenous dissemination
- Direct extension from adjacent structures
Mycobacterial factors:
- Virulence factors
- Immune evasion mechanisms
- Bacterial persistence

Immunological Response:

Initial response:
- Innate immunity activation
- Macrophage recruitment
- Cytokine production
Granuloma formation:
- T-cell mediated response
- Epithelioid cells
- Giant cell formation
- Caseous necrosis

Disease Progression:

Early stage:
- Lymph node enlargement
- Inflammatory changes
Late stage:
- Caseation
- Liquefaction
- Cold abscess formation
- Sinus tract development

Clinical Features

Symptoms:

Local symptoms:
- Painless lymph node enlargement
- Progressive node growth
- Node tenderness (in acute cases)
- Matted nodes
Systemic symptoms:
- Low-grade fever
- Weight loss
- Night sweats
- Fatigue
- Poor appetite

Physical Findings:

Lymph node characteristics:
- Size: 2-8 cm typical
- Consistency: Firm to fluctuant
- Mobility: Initially mobile
- Surface: Smooth to irregular
Distribution patterns:
- Cervical (most common)
- Submandibular
- Axillary
- Inguinal
- Mediastinal

Staging & Classification

Clinical Stages:

Stage 1:
- Enlarged, firm, mobile nodes
- No periadenitis
Stage 2:
- Large, rubbery nodes
- Early periadenitis
- Matted nodes
Stage 3:
- Central softening
- Cold abscess
Stage 4:
- Collar stud abscess
- Sinus formation
Stage 5:
- Scar formation
- Calcification

Diagnosis

Initial Evaluation:

History:
- Duration of symptoms
- TB contact
- Previous treatment
- Risk factors
Physical examination:
- Complete lymph node mapping
- Associated findings
- Constitutional symptoms

Diagnostic Studies:

Imaging:
- Ultrasonography:
  - Node characteristics
  - Matting patterns
  - Liquefaction
- CT/MRI:
  - Deep node involvement
  - Extent of disease
  - Complications
Laboratory studies:
- FNAC (Fine Needle Aspiration Cytology)
- Excisional biopsy
- AFB smear
- Culture
- PCR testing
- Histopathology

Treatment

Medical Management:

First-line regimen:
- Intensive phase (2 months):
  - Isoniazid (H)
  - Rifampicin (R)
  - Pyrazinamide (Z)
  - Ethambutol (E)
- Continuation phase (4-7 months):
  - Isoniazid
  - Rifampicin

Surgical Management:

Indications:
- Diagnostic uncertainty
- Large fluctuant nodes
- Sinus tract formation
- Treatment failure
Procedures:
- Incision and drainage
- Excisional biopsy
- Complete node excision

Monitoring & Follow-up

Clinical Monitoring:

Regular assessment:
- Node size
- New node development
- Constitutional symptoms
- Treatment response
Follow-up schedule:
- Weekly for first month
- Monthly thereafter
- Extended follow-up for complications

Treatment Response:

Expected timeline:
- Symptom improvement: 2-4 weeks
- Node regression: 3-6 months
- Complete resolution: 9-12 months
Paradoxical reaction:
- New node enlargement
- New suppuration
- Management modification

Complications & Prognosis

Common Complications:

Local complications:
- Abscess formation
- Sinus development
- Scarring
- Calcification
Systemic complications:
- Disseminated TB
- Drug resistance
- Immune reconstitution

Prognosis Factors:

Favorable factors:
- Early diagnosis
- Proper treatment
- Good compliance
- Immunocompetence
Poor prognostic factors:
- HIV co-infection
- Drug resistance
- Extensive disease
- Poor compliance

Special Considerations

HIV Co-infection:

Modified presentation:
- Rapid progression
- Multiple site involvement
- Atypical features
Treatment modifications:
- Extended duration
- Drug interactions
- Immune reconstitution

Prevention Strategies:

Primary prevention:
- BCG vaccination
- Contact screening
- Environmental control
Secondary prevention:
- Early diagnosis
- Proper treatment
- Contact tracing

Tuberculous Lymphadenitis (Scrofula) in Children

Key Points

Most common form of extrapulmonary TB (30-40%)
More prevalent in children aged 0-5 years
Cervical nodes most commonly affected (60-80%)
Better prognosis compared to other forms of TB
Strong association with HIV co-infection

Epidemiology

Global Distribution:
- Higher prevalence in developing countries
- 15-20% of all TB cases in endemic areas
- Female:Male ratio = 1.5:1
Risk Factors:
- Young age
- HIV infection
- Malnutrition
- Low socioeconomic status
- Immunosuppression
- Living in TB endemic areas

Detailed Pathophysiology

Routes of Infection

Primary Routes:
- Lymphatic spread from primary focus
- Hematogenous dissemination
- Direct extension from adjacent structures
- Through tonsillar route (cervical nodes)
Node Involvement Pattern:
- Unilateral (70%)
- Bilateral (30%)
- Single group vs multiple groups

Pathological Stages

Stage 1 - Lymphadenitis:
- Node enlargement
- Preserved architecture
- Minimal inflammation
Stage 2 - Periadenitis:
- Periadenitis development
- Matted nodes
- Capsular thickening
Stage 3 - Cold Abscess:
- Central caseation
- Liquefaction
- Abscess formation
Stage 4 - Collar Stud Abscess:
- Subcutaneous extension
- Sinus formation
- Skin involvement

Clinical Manifestations

Node Characteristics

Common Sites:
- Cervical (60-80%)
- Submandibular (15-20%)
- Axillary (10-15%)
- Inguinal (5-10%)
- Mediastinal
- Mesenteric
Physical Characteristics:
- Size: 2-8 cm typically
- Consistency: Firm to fluctuant
- Mobility: Initially mobile, later fixed
- Temperature: Usually non-tender, no local heat

Clinical Progression

Early Stage:
- Firm, discrete nodes
- Mobile, non-tender
- Normal overlying skin
Intermediate Stage:
- Matted nodes
- Limited mobility
- Periadenitis
Late Stage:
- Fluctuation
- Skin changes
- Sinus formation
- Scarring

Systemic Symptoms

Constitutional:
- Low-grade fever
- Weight loss
- Fatigue
- Night sweats
Associated Features:
- Cough (if pulmonary involvement)
- Dysphagia (if deep cervical)
- Hoarseness
- Stridor (rare)

Diagnostic Approach

Imaging Studies

Ultrasound:
- Hypoechoic nodes
- Intranodal necrosis
- Matted appearance
- Surrounding edema
- Power Doppler features
CT/MRI:
- Central necrosis
- Rim enhancement
- Calcification
- Perinodal extension

Tissue Diagnosis

FNAC:
- First-line investigation
- Sensitivity: 80-90%
- Cytological patterns:
  - Epithelioid granulomas
  - Caseous necrosis
  - Langhan's giant cells
Excisional Biopsy:
- Gold standard
- Better yield than FNAC
- Provides tissue for all tests

Laboratory Tests

Microbiological:
- AFB smear
- Gene Xpert MTB/RIF
- Culture (solid/liquid media)
- PCR for TB DNA
Other Tests:
- Mantoux test
- IGRA
- Complete blood count
- ESR and CRP
- HIV testing

Treatment Protocol

Medical Management

First-line ATT:
- Intensive Phase (2 months):
  - Isoniazid (H): 10 mg/kg/day
  - Rifampicin (R): 15 mg/kg/day
  - Pyrazinamide (Z): 35 mg/kg/day
  - Ethambutol (E): 20 mg/kg/day
- Continuation Phase (4 months):
  - Isoniazid + Rifampicin
  - Total duration: 6 months

Surgical Management

Indications:
- Diagnostic uncertainty
- Large fluctuant nodes
- Sinus tract formation
- No response to ATT
- Compression symptoms
Procedures:
- FNAC
- Incision and drainage
- Excisional biopsy
- Complete node excision

Comprehensive Management

Response Monitoring

Clinical Response:
- Node size reduction
- Resolution of symptoms
- Weight gain
- Activity improvement
Paradoxical Response:
- Temporary enlargement
- New node appearance
- Usually 2-3 months after ATT

Complications Management

Local Complications:
- Abscess formation
- Sinus development
- Scarring
- Calcification
Drug-related:
- Hepatotoxicity
- Skin reactions
- Visual disturbances

Special Clinical Scenarios

HIV Co-infection

Modified Approach:
- Extended treatment duration
- Higher drug resistance risk
- More frequent monitoring
- Timing of ART initiation

Drug-resistant Cases

Management:
- Drug sensitivity testing
- Second-line drugs
- Extended duration
- Expert consultation

Disseminated Disease

Additional Measures:
- Systemic evaluation
- Extended treatment
- Close monitoring
- Supportive care

Follow-up Protocol

Monitoring Schedule

Clinical Monitoring:
- Monthly node assessment
- Weight monitoring
- Symptom evaluation
- Treatment adherence
Investigation Follow-up:
- Liver function tests
- ESR/CRP trending
- Ultrasound if needed

Treatment Outcome

Favorable Response:
- Node size reduction
- Symptom resolution
- No new nodes
- Weight gain
Poor Response:
- Persistent/enlarging nodes
- New node development
- Persistent symptoms
- Development of complications

Disclaimer

The notes provided on Pediatime are generated from online resources and AI sources and have been carefully checked for accuracy. However, these notes are not intended to replace standard textbooks. They are designed to serve as a quick review and revision tool for medical students and professionals, and to aid in theory exam preparation. For comprehensive learning, please refer to recommended textbooks and guidelines.

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Tuberculous Lymphadenitis in Children